Anaphylaxis

Question 1

What are two other systems that can be involved in anaphylaxis and their symptoms?

Answer 1

Genitourinary: uterine cramps, incontinence, bleeding; CNS: seizures, confusion, dizziness

Question 2

What are the doses of IM adrenaline in children?

Answer 2

1:1000 IM: 1mg = 1mL. Divide into 3 age groups: <6 years = 0.15mL (0.15mg); 6-12 = 0.3mL (0.3mg); >12 = 0.5ml (0.5mg). Repeat after 5 minutes if not improving (draw up and have ready to go) - could be after 3 minutes if required. Often one or rarely two extra doses are needed. Use a 1mL syringe.

If <10kg try to give exact weight based dose if possible. However if likely to cause delay in patient with severe symptoms or who is deteriorating then give 0.1mL (or 0.15mL also ok - any SE expected to be mild and transient)

Question 3

What are other drugs used in anaphylaxis after IM adrenaline to treat symptoms?

Answer 3

1. N saline bolus of 20ml/kg if still hypotensive after adrenaline - maximum 50mL/kg in first 30 minutes; 2. Nebulised adrenaline for stridor/upper airway obstruction or severe bronchospasm: 5mg (5 x 1mL ampoules); 3. Bronchodilators e.g. 8-12 puffs of salbutamol 100mcg with spacer or 5mg nebulised salbutamol for peristent wheeze

Question 4

What should be done re steroids or antihistamines?

Answer 4

Prednisone: 1mg/kg PO max 50mg or hydrocortisone 5mg/kg (max 200mg) (followed by a 2 day course at home); Only non-sedating antihistamines

Question 5

What is the dose of anaphylaxis in pregnant women?

Answer 5

0.3mg

Question 6

What position should a pregnant woman be laid in?

Answer 6

L lateral

Question 7

Why is positioning important?

Answer 7

Any sudden sitting and standing can cause fatality within minutes. The person with primary respiratory symptoms may prefer to sit and this may support ventilation/breathing. Monitor closely and if any alteration in consciousness or hypotension, lie immediately flat. The person must not walk to the ambulance even after recovery.

Question 8

Describe an adrenaline infusion?

Answer 8

1mL of 1:1000 in 1L of N saline. Administer at 5mL/kg/hour. check giving set but usually 20 drops per mL. In liaison with emergency physician.

Question 9

When and how should glucagon be used?

Answer 9

For persistent hypotension especially for patients with heart failure or on beta blockers: 1-2mg IM